A Casper woman will spend time in prison for poisoning her stepmother with eye-drops.

Eighteen-year-old Alexis Jennings was sentenced to serve two-to-four years at the Wyoming Women's Center in Lusk, after pleading no contest to one charge of aggravated assault.

Prosecutors say from July through November of 2012, Jennings tried to poison her stepmother, by lacing her coffee and tea with Visine.

Prosecutors say Jennings used as much as a quarter of a bottle per drink, and went through as many as 20 bottles during that time.

A law enforcement official said that Jennings was upset that her stepmother, was unable to keep a secret, and that she got the poisoning idea from an unrelated story she saw on the internet.